REST API phone lookup field?

[Jan_Unar]

I am trying to find leads by their phone number using Marketo REST API (Get Leads by Filter Type) but Phone number is not supported. Why is that and is there a way to solve this? Thank you.

[SanfordWhiteman]

Only certain system fields are allowed. With Phone, perhaps it's disallowed because of assumptions about cardinality (when every employee at the same company gets the main number, for example) and/or formatting (if you don't pass the value through a reformatting webhook, et al., there's no way to predict formatting of the same underlying #).

But regardless of the reason, you can't use it.

What you can use is a custom String that you keep in sync with the system Phone using a Smart Campaign.

[Jay_Jiang]

As mentioned above, you can still make it work as you can filter by any custom field. Just create a custom field, copy the data from the system Phone field into your custom field and you'll be able to use that field in your requests